Processing of Cigar Lake ore in the McClean Lake mill

The Cigar Lake mine is scheduled to begin production in 2002. With an average ore grade of 25% U3O8, special considerations will be required in both mining and processing. The ore will be transported as a slurry in specially designed containers. Processing will initially begin at the McClean Lake mill while mining methods are proven and capabilities established. This paper discusses the specific issues and challenges related to processing the Cigar Lake high-grade ore at the McClean Lake mill. Some new facilities will be required, such as ore receiving and an oxygen plant. However, many existing circuits will just require varying degrees of modifications including leaching, countercurrent decantation (CCD), solvent extraction, molybdenum removal, tailings neutralization and tailings placement. Technical issues as well as specific considerations for safety and radiation are reviewed in this paper.